ARC-1200 degraded array question

Hello, I'm running an Areca ARC-1200 card in a Dell Windows 7 system in a two-drive RAID 1 configuration.

Yesterday I got my first-ever alert from the card, and it's unclear to me whether it was the card faulting or the drive faulting. How the heck can I tell?

Channel 2 (the one that faulted) was marked failed in the ARCHTTP UI. I activated it and it was then marked degraded, presumably making it a candidate for background rebuilding (I guess). But then, mistakenly, I clicked the activate button on channel 1, and now they're both marked degraded. I don't know for sure, but it looks to me like this array is not going to be rebuilding itself now. Am I right about that?

Thanks for any info or advice you can share.

Tom